The present invention pertains to vacuum systems for recovering hazardous liquid acid spills. A critical element of the invention is the neutralization of vapors from acid liquids being vacuum-transported such that the vapors may pass through a vacuum pump and into the surrounding ambient air without risk or damage to the pump or nearby humans.
Liquid acid spills pose particular difficulties among the great variety of hazardous waste problems. Conventionally, liquid acid spills are most typically neutralized after or during recovery. This process itself is problematic due to the potential generation of both hydrogen gas and heat from what is an exothermic event. As well, the result of neutralization is an increased volume of waste requiring disposal. However, recovery of un-neutralized acid liquid spills is difficult and may be dangerous due to the nature of acids.
Various vacuum systems with the potential for use in recovery of liquid acid spills are known and available. However, an inherent element of vacuum systems for this use is the movement and mixing of surrounding air with the transferred liquid. This is particularly true where a spill is relatively uncontained on a surface such as the ground and therefore has a low depth. To draw such a spill into a vacuum system requires a large volume of entraining transport air. This relatively large volume of air must pass through the vacuum pump and be exhausted in some manner into the ambient air. Prior vacuum recovery systems are not safe for use with recovery of acid liquids because the associated entraining air volume itself becomes a hazard due to the entrained acid liquid vapors. Because, these liquid vapors are acidic, they may degrade or destroy the pump equipment. As well, when exhausted into an occupied space, they may pose a hazard to both surrounding equipment and persons.
A large portion of acid liquid spills, and other situations requiring transfer of acid liquids, involve relatively small volumes of liquid. In addition, these events often occur in circumstances where the location is not planned or controlled, such as accidental spills in industrial facilities. In these circumstances, it is desirable to have available a portable recovery device and methods that are operable by a minimum of personnel, with a minimum of training and instruction, and with readily available power. What is needed is a simple, vacuum recovery system for acid liquids that may be used without degrading the surrounding air and is applicable for low capacity systems.